Electrical switch with multiple contact rails



April 16, 1968 L. c. HOY ETAL 3,378,654

ELECTRICAL SWITCH WITH MULTIPLE CONTACT RAILS Filed Feb. 27, 1967 2 Sheets-Sheet l F1112 v 5 FIG. 1 E1623 ,LO-FRONT Mb m-maur REA]? 428 DE-FOG lnvturwes Leland C. Hay and Kory: Hazek WM/M April 16, 1968 c. HOY ETAL ELECTRICAL SWITCH WITH MULTIPLE CONTACT RAILS 2 Sheets-Sheet 1 FJ'G. 10

Filed Feb. 27, 1967.

- FIG.

United States Patent 3,378,654 ELECTRICAL SWITCH WITH MULTIPLE CONTACT RAILS Leland C. Hoy, Skokie, and Borys Hazek, Mount Prospect, Ill., assignors to Indak Manufacturing Corp.,

Northbrook, 111., a corporatiouof Illinois Filed Feb. 27, 1967, Ser. No. 618,901 16 Claims. (Cl. 200-16) ABSTRACT OF THE DISCLOSURE An electrical switch having a plurality of contact-ors adapted to ride along a plurality of tracks, each of which is formed by two or more rail segments, certain rail segments on adjacent tracks being preferably formed integrally with each other, the oontactors preferably being adapted to connect four terminals together in at least one position of the switch.

In certain aspects, the present invention may be regarded as an improvement upon the invention disclosed and claimed in the Hoy and Hazek Patent No. 3,223,794, patented Dec. 14, 1965, and entitled, Multiple Position Electrical Switch With Contact Rails and Dummy Contact Pressure Stabilizers.

This invention relates to multiple position electrical switches adapted to control the connections between a multiplicity of terminals or circuits. Such switches find many applications including, for example, the control of automotive heating and air conditioning systems.

Many switching applications involve the problem of interconnecting four different terminals in at least one position of the switch, while establishing various connections between the four terminals, as well as other terminals, in other positions of the switch. The switches disclosed and claimed in the above-mentioned Hoy and Hazek Patent No. 3,223,794 represent one highly successful approach to the solution of the problems involved in such switching applications.

One object of the present invention is to provide a new and improved switch construction which is even more flexible and versatile than hereto-fore, so as to be capable of carrying out highly complex switching operations.

The present invention involves the provision of a switch having a plurality of contactors, all of which are mounted on and movable with an insulating carriage. The contactors ride along a plurality of tracks, each of which is formed by at least two rail segments mounted on an insulating support. Each cont-actor is adapted to form a conductive bridge between the rail segments which are mounted on opposite sides of its particular track. Preferably, the rail segments are formed on metal plates which are mounted on an insulating board or the like. Certain rail segments along adjacent tracks are preferably formed integrally with each other. The construction of the present invention is highly compact and easy to manufacture, yet is extremely versatile so that the most complex switching applications can be handled.

Further objects and advantages of the present invention will appear from the following description, taken with the accompanying drawings, in which:

FIG. 1 is a side elevation of an electrical switch to be described as an illustrative embodiment of the present invention.

FIG. 2 is a rear elevation of the switch.

FIG. 3 is a front elevation thereof.

FIG. 4 is an enlarged rear elevation of the switch with the insulating board removed therefrom, the view being taken generally as indicated by the line 44 in FIG. 1.

FIG. 5 is an enlarged front elevation of the insulating 3,378,654 Patented Apr. 16, 1968 board, with the various contact rails mounted thereon, the ,view being taken generally as indicated by the line 55 in FIG. 1.

FIG. 6 is a rear view of the insulating carriage for the switch.

FIG. 7 is a front view of the carriage.

FIG. 8 is a bottom view of the carriage.

FIG. 9 is a longitudinal section, taken generally along the line 99 in FIG. 2.

FIG. 10 is a transverse section, taken generally along the line 1010 in FIG. 2.

FIG. 11 is an enlarged transverse section, taken generally along the line 1111 in F161. 4.

FIG. 12 is an enlarged perspective view showing one of the movable contactors for the switch.

FIG. 13 is an enlarged perspective view representing each of the other two contactors.

As already indicated, the drawings illustrate an electrical switch 20 which is especially well adapted for auto motive service, but will find many other applications. The illustrated switch 20 comprises a housing 22, preferably made of sheet metal. As shown, the housing 22 comprises a front wall 24, side walls 26 and 28, and end walls 30 and 32. It will be seen that the housing 22 is generally rectangular in shape. When the switch 20 is 'fully assembled, the rear side of the housing 22 is closed by a contact supporting member or plate 34, preferably made of an electrically insulating material. The plate or board 34 is suitably secured to the housing 22. As shown, the housing 22 is formed with a plurality of tabs 36 which extend rearwardly through slots or notches 38 in the plate 34. The tabs 36 are bent or clinched inwardly behind the plate 34.

As shown in FIG. 4, a carriage 40' is movably mounted within the housing 22. In the illustrated construction, the carriage 40 is slidable longitudinally within the housing 22. As shown, the carriage 40 is generally rectangular in shape. The front wall 24 and the side walls 28 serve as guides for the carriage 40. The longitudinal movement of the carriage 40 is limited by the end walls 30 and 32. Preferably, the carriage 40 is made of an electrically insulating material, such as a suitable plastic.

Most electrical switches are provided with operating levers, handles, or other manually operable control elements. In most instances, the lever or the like is built into the switch. However, the illustrated switch 22 is adapted to be operated by an external lever or other operating member, indicated diagrammatically at 42 in FIG. 1. The operating lever may be generally similar in shape and function to the lever shown in the above-mentioned Hoy and Hazek Patent N0. 3,223,794.

It will be seen from FIGS. 2 and 3 that the front wall 24 of the housing 22 is formed with a longitudinal slot 44, through which the external operating lever 42 is adapted to extend into the housing. The front side of the carriage 40 is formed with a recess or slot 46, adapted to receive the rear end of the operating lever. As shown to best advantage in FIG. 9, the slot 46 extends only part way through the carriage 40. A suitable mounting bracket 48 is suitably secured to the front wall 24 of the housing 22.

As will be explained in greater detail presently, the carriage 40 is movable to a series of operating positions within the housing 22. Detent elements are provided on the carriage 40 and the housing 22 to detain the carriage in its various positions. The detent elements on the carriage 40 preferably take the form of projections 50 extending forwardly therefrom. Detent grooves or recesses 52 are formed in the front wall 24 to receive the detent projections 50. The illustrated carriage 40 is provided with four of the detent projections 50, as will be evident from FIG. 7.

The carriage is adapted to carry a plurality of movable contactors. Three contactors 54, 56 and 58 are provided in the illustrated construction. However, the number of contactors may be varied to suit various applications.

The contactors 54, 56 and 58 are adapted to engage a relatively complex contact structure or assembly 60 mounted on the plate or board 34. The insulating plate 34 provides a convenient support for the contact structure 60', but other types of insulating supports could be provided. The contact structure 60 will be described in detail presently.

Means are provided to bias the contactors rearwardly so that they will be pressed into engagement with the contact structure 60. As shown, three coil springs 62 are compressed between the carriage 40 and the contactors 54, 56 and 58. The springs 62 are seated in sockets or recesses 64, 66 and 68, formed in the carriage 40. In addition to pressing the contactors rearwardly, the springs 62 bias the carriage 40 forwardly so that the detent projections 50 will be resiliently pressed into the detent notches or recesses 52.

The contactors 54, 56 and 58 are guided for movement from front to rear relative to the carriage 40, so that the contactors are able to ride along the various elements of the contact structure 60. As shown to best advantage in FIGS. 11, 12 and 13, each of the contactors 54-58 is formed with a pair of guide tabs or prongs 70 which are bent therefrom toward the front of the switch 20. Recesses or slots 72 are formed in the rear side of the carriage 40 so as toreceive the tabs 78'. It will be evident that the tabs 70 are slidably guided in the slots 72 for movement from front to rear.

The rear side of the illustrated carriage 40 is formed with a series of longitudinal guide ribs 73 which project 1 toward the insulating plate 34 but are spaced therefrom to provide for the detenting movement of the carriage 40. The provision of the ribs 73 results in the formation of three grooves 74, 76 and 78 in which the three contactors 54, 56 and 58 are received.

The contactor 54 is shown in FIG. 12. The contactors 56 and 58 are identical in construction. One of them is shown in FIG. 13. Each of the contactors 54-58 comprises a plate-like body 80. The tabs 78 are bent from the body 80 generally perpendicular thereto. It is preferred to form each of the contactors 54-58 with a rearwardly projecting shoe portion or rider 82. As shown in FIGS. 12 and 13, the shoe portion is stamped or struck from the body 80. Each of the illustrated shoe portions 82 is generally V-shaped in cross section, with rounded contours. The contactor 54 differs from the contactors 56 and 58 in that the shoe portion 82 is differently oriented relative to the positions of the tabs 70. In other respects, the contactor 54 is similar to the contactors 56 and 58.

In general, the illustrated contact structure 60- comprises a plurality of tracks, along which the contactors are movable. Three such tracks 84, 86 and 88 are illustrated in FIG. 5, for receiving the respective contactors 54, 56 and 58.

The tracks 84, 86 and 88 are provided by a plurality of contact rail segments. The contactors 54-58 are adapted to act as conductive bridges between the rail segments on opposite sides of the corresponding tracks 84-88. Generally speaking, each of the tracks 84-88 comprises at least two rail segments on opposite sides thereof. The rail segments vary in length and position, to accomplish various switching operations.

It will be seen from FIG. 5 that the illustrated track 84 is centrally disposed on the insulating board 34, for engagement by the centrally disposed contact 54. The illustrated track 84 comprises rail segments 84a, 84b, 84c, 84d and 846, all made of metal or conductive material. It will be understood that the number and arrangement of the rail segments may be varied. As shown to best advantage in FIG. 11, the illustrated rail segments 84u-d are preferably rounded and generally semi-cylindrical in shape. The rail segments may be stamped or otherwise formed from sheet metal.

The rail segments 84a and b are on one side of the track 84, while the rail segments 840, d, and e are on the opposite side of the track. It will be seen that the rail segments 84a and c are connected together and are preferably formed integrally as portions of a single sheet metal plate or member 91. The rail segments 84b, 0 and d are formed as portions of other sheet metal plates or members 92, 93 and 94.

The illustrated track 86 comprises rail segments 86a, 86b, and 860. The segment 86a is on one side of the track 86, while the segments 86b and c are on the opposite side; it will be seen that the rail segments 86a and b are connected together and preferably are formed integrally with the sheet metal plate 93, on which the rail segment 84d of the adjacent track is also formed. The illustrated rail segment 860 is formed on a separate sheet metal plate 95.

The third track 88 comprises rail segments 88a, 88b, 88c, and 88d. The segments 88a and b are on one side of the track 88 while the segments 88c and d are on the opposite side. It will be seen that the segments 88a and c are connected together and preferably are formed integrally on a sheet metal plate 96. The segments 88b and 88d are connected together and also are connected to the rail segment 84b, all three segments being formed integrally with the sheet metal plate 92. I

Suitable terminals or lugs 101-106 are connected to the corresponding metal contact plates 91-96 and are mounted on the rear side of the insulating board 34. The terminals 101-186 are suitably secured to the contact plates 91-96, as by means of rivets 188 extending through holes in the insulating board 34. To prevent rotation of the plates 91-96 about the rivets 188, the plates are formed with tabs or lugs 110 which project into holes or recesses 112 formed in the board 34.

In addition to the conductive rail segments 84a-e, the track 84 comprises a pair of insulating rail segments 114a and b with a groove 114 c therebetween. The rail segments 114a and b are punched, pressed or otherwise formed from the insulating plate 34. Preferably, the rail segments 114a and b are formed by a punch press operation. The insulating rail segments could also be molded integrally with the insulating plate. It will be seen that the insulating rail segments 114a and b are interposed between the conductive segments 84a and d, at one end of the track 84, and the segments 84b and e, at the opposite end of the track 84.

The rearwardly projecting shoes or riders 82 on the contactors 54-58 ride smoothly along the tracks 84-88 so as to engage the rail segments on the opposite sides of the tracks. Thus, the shoes 82 form conductive bridges between the rail segments on the opposite sides of the tracks.

It will be understood that the arrangement of the conductive rail segments may be varied to suit various switching operations. Thus, the switch may be arranged for use with a variety of electrical circuits. One such circuit is indicated diagrammatically in FIG. 5, merely by way of example. This circuit will serve to illustrate the operation of the switch.

The illustrated circuit is used to control the heating and air conditioning system of an automobile or other automotive vehicle. It will be seen that one side of the automotive battery is connected to the terminals 102 and 103, and thus to the contact plates 92 and 93. The other side of the battery 120 is grounded. The clutch solenoid 122 of the automotive air conditioner is connected between the contact plate 96 and ground. One side of the main blower motor 124- is grounded. A speed control resistor 126 is connected between the contact plate 91 and the ungronnded side of the motor 124. Similarly, another speed control resistor 128 is connected between the contact plate 95 and the ungrounded side of the motor 124. A de-icing blower motor 130 is connected between the contact plate 94 and ground.

To facilitate the description of the operation of the switch, the contactors 54, 56 and 58 are shown in phantom in FIG. 5. The contactors are shown in their OFF position, which happens to be the uppermost position, as the switch is oriented in FIGS. 4 and 5. In this position, the contactor 54 engages the rail segments 84a and c, which are connected together in any event, so that the contactor has no effect. The rail segments 84a: and c merely serve as guides for the contactor 54.

The contactor 56 engages only the rail segment 86b and thus has no effect. The contactor 58 engages the rail segments 88a and c, which merely act as guides, inasmuch as these segments are connected together in any event.

From the OFF position, the carriage 40 may be moved downwardly by one detent notch to the second position, which is designated LO-FRONT in FIG. 4. The designation means that a low volume of air is to be supplied to the front seat. In this position, the contactor 54 forms a bridge between the rail segments 84a and d, so that the blower motor 124 is energized through the resistor 126. The contactor 56- is between the rail segments 86a and b, which are connected together in any event, so that the contactor has no effect. The contactor 58'forms a bridge between the rail segments 88a and d, so that the clutch solenoid 122 is energized by the battery 120.

Next, the carriage 40 may be moved down by another detent notch, to the position designated HI-FRO'NT in FIG. 4. In this position, the contactor 54 still forms a bridge between the rail segments 84a and b, with the same effect as before. However, the contactor 56 now forms a bridge between the rail segments 86a and c, with the result that the blower motor 124 is energized through the resistor 128, in parallel with the resistor 126. Thus, the speed of the motor 124 is increased. The contactor 58 still forms a bridge between the rail segments 88a and b, so that the energization of the clutch solenoid 122 is maintained.

From the HI-FRONT position, the carriage 40 may be moved down by another detent notch to the position designated REAR in FIG. 4. In this position, the contactor 54 is between the insulating rail segments 114a and b and thus has no effect. The contactor 56 continues to form a bridge between the rail segments 86:: and c, so that the blower motor 124 is energized through the resistor 128 only. The speed control resistors 126 and 128 preferably have different values, so that the motor 124 operates at a different speed than it did in the LO-FRONT position of the switch. Preferably, the resistor 128 has a lower value than the resistor 126, so that a higher motor speedis produced.

Next, the carriage 40 may be moved down by another detent notch, to the position designated DE-FOG in FIG. 4. It happens that in this position the switching functions are the same as in the previous position, designated REAR. The associated control system merely makes mechanical or other changes in the heating and air conditioning system. However, the construction of the switch could be varied so as to produce different switching functions in the two positions.

Finally, the carriage 40 is moved down by another detent notch, to the position designated DE-ICE in FIG. 4. In this position, the contactor 54 forms a bridge between the contact segments 84b and 2, with the result that the second blower motor 130 is energized directly from the battery 120, so as to operate at maximum speed. The contactor 56 continues to act as a bridge between the rail segments 86a and 0, so that the blower motor 124 is still energized through the resistor 128. The contactor 58 is between the rail segments 88b and d, which are connected together in any event. Thus, the contactor 58 has no effect, and the clutch solenoid 122 is deenergized.

It should be noted that the switch is adapted to connect four terminals together in at least one position of the switch, in this case the third position, designated HI- FRONT. In this position, as already explained, the contactors 54 and 56 form the connections between the contact plates 91, 93 and The contact plates 92 and 93 are connected together by virtue of the fact that both of them are connected to the ungrounded side of the battery 120. The contactor 88 establishes a connection between the contact plates 92 and 96. Thus, the contact plates 91, 92, 93, 95 and 96 are all connected together, but the contact plates 92 and 93 are connected together by the external wiring to the battery, so that the effect of the switch is to establish a four-point contact. This is a valuable feature, because it is a difficult problem in switch design to achieve a four-point contact.

It will be evident that the switch construction of the present invention is highly flexible and versatile. The details of the switch construction may readily be varied so as to achieve a wide variety of complex switching operations. Inasmuch as each contactor engages only two rail segments at any one time, the engagement is positive, and the contactor forms a highly reliable conductive bridge between the two rail segments. The projecting shoe 82 of the contactor seats between the rail segments and is automatically aligned therewith.

Various other modifications, alternative constructions, and equivalents may be employed without departing from the true spirit and scope of the invention, as exemplified in the foregoing description and defined in the following claims.

We claim:

1. In an electrical switch,

the combination comprising a housing,

a carriage, movable in said housing,

a plurality of contactors mounted on said carriage,

and a plurality of tracks mounted in said housing for receiving said contactors,

each of said tracks comprising at least two conductive rail segments mounted on opposite sides thereof and engageable by the corresponding contactor,

said contactor being adapted to form a conductive bridge between said rail segments.

2. In an electrical switch,

the combination comprising a housing,

a carriage, movable in said housing,

a contactor mounted on said carriage,

and a track in said housing for receiving said contactor,

said track comprising at least two conductive rail segments on opposite sides of said track and engageable by said contactor,

and at least one insulating rail segment extending along at least one side of a portion of said track.

3. In an electrical switch,

the combination comprising a housing,

a carriage, movable in said housing,

and a track in said housing for receiving said contactor,

said track comprising at least two conductive rail segments on opposite sides of said track,

and an insulating member having a groove therein for receiving and guiding said contactor.

4. In an electrical switch,

the combination comprising a housing,

a carriage, movable in said housing,

a contactor mounted on said carriage,

and a track in said housing for receiving said contactor,

said track comprising at least two conductive rail segments on opposite sides of said track,

said contactor having a generally V-shaped shoe portion for riding between and engaging said rail segments.

5. The combination of claim l, in which certain of said rail segments along adjacent tracks are connected together.

6. The combination of claim 1, in which certain of said rail segments along adjacent tracks are formed integrally with each other.

7. The combination of claim 1, including at least one insulating rail segment extending along one of said tracks.

8. The combination of claim 1, including a pair of insulating rail segments on opposite sides of one of said tracks for guiding the corresponding contactor.

9. The combination of claim 1, in which at least one of said tracks includes an insulating member having a groove therein for guiding the corresponding contactor.

10. The combination of claim 1, including three of said contactors mounted on said carriage, and three of said tracks for receiving the respective contactors.

11. The combination of claim 1, including three of said contactors mounted on said carriage, and three of said tracks for receiving the respective contactors,

at least one rail segment of each of said tracks being connected to one rail segment of the adjacent track.

12. The combination of claim 1, in which at least one of said contactors comprises a V-shaped shoe portion for riding between and engaging the corresponding rail segments.

13. The combination of claim 2, including a pair of References Cited UNITED STATES PATENTS 3,223,794 12/1965 Hoy et al. 200l6 3,329,778 7/1967 Bedocs 200l6 ROBERT K. SCHAEFER, Primary Examiner.

J. R. SCOTT, Assistant Examiner. 

